Neurosurgery and Brain Health Brain Mapping Pinpoints Source of Epileptic Seizures By Neurosurgery, June 3, 2015 Epilepsy is a condition in which bursts of electricity in the brain disrupt its normal functioning and cause seizures. It is commonly diagnosed in children or in elderly people, but it can develop at any time. What Is Brain Mapping? To help pinpoint the source of these electrical bursts in the brain, doctors use a process called brain mapping. By viewing and stimulating different areas of the brain, the doctor can map out what areas of the brain control what functions of the body. This process identifies abnormalities, tumors, lesions, or injuries in the brain, as well as any unusual activity. What Types of Brain Scans Are Used? Magnetoencephelography (MEG) Magnetoencephelography (MEG) is a noninvasive brain mapping technique, meaning it is done outside the body. MEG maps brain activity by using the magnetic fields created by the brain. There are no injections or radioactivity involved, so it’s safe for kids as well as adults. Electroencephalogram (EEG) A MEG scan is usually combined with an electroencephalogram (EEG) to get an accurate idea of the inner workings of the brain. Add a magnetic resonance imaging (MRI) scan, which shows the brain structure, and your physician can see a detailed picture of what’s going on and where. What Happens During MEG? The MEG scan is performed in a room that is shielded from magnetic or electrical activity. You will need to remove all metal jewelry or clothing. A technician will attach coils to your head with tape. Then the MEG machine fits over your head like a helmet. You may sit in a chair or lie down and can sleep during the scan, but you must be as still as possible throughout. It takes 30 minutes to over an hour to complete. The machine is quiet and records brain activity while you wait. Sometimes, the technician performing the scan may stimulate areas of the brain to get a more accurate map. Why Is Brain Mapping Important? In addition to helping determine the cause of epileptic seizures, brain mapping serves as a guide for surgery. The surgeon can use the images from MEG, EEG, and MRI to pinpoint the tumor or lesion. The map also helps the surgeon avoid the well functioning areas of the brain and focus on those that are causing trouble. To learn more about brain mapping for epilepsy management and treatment, visit the UPMC Department of Neurosurgery.